Object is rotated in edit mode?
The character is posed: the bones of its armature are not in rest pose (at least one of them). When you enter edit mode, the mesh is shown in its rest pose.

You can enable these two buttons to have your armature have effect in edit mode also:



Or you can temporarily disable the armature modifier to show both meshes in rest pose, or even select all bones and press Alt + G , Alt + R, Alt + S to reset all poses of the bones or, at last, select the armature and in its properties panel choose rest position instead of pose position.